Conventionally, in the manufacture of semiconductor devices, micro-processing by lithography using a photoresist has been carried out. The micro-processing is a processing method comprising forming a thin film of a photoresist on a semiconductor substrate such as a silicon wafer or the like, irradiating actinic rays such as ultraviolet rays through a mask pattern on which a pattern for a semiconductor device is depicted, developing it to obtain a photoresist pattern, and etching the substrate using the photoresist pattern as a protective film, thereby forming fine unevenness corresponding to the pattern on the surface of the substrate. However, in recent progress in high integration of semiconductor devices, there has been a tendency that shorter wavelength actinic rays are being used, i.e., ArF excimer laser beam (193 nm) has been taking the place of KrF excimer laser beam (248 nm). Along with this change, influences of random reflection and standing wave of actinic rays from a substrate have become serious problems. Accordingly, it has been widely studied to provide an anti-reflective coating between the photoresist and the substrate (bottom antireflective coating) in order to resolve the problem. As the anti-reflective coating, from a viewpoint of easy of use, many considerations have been done on organic anti-reflective coatings made of a light absorbing substance and a polymer compound and the like. For example, they are described in U.S. Pat. No. 5,919,599 and U.S. Pat. No. 5,693,691, and the like.
The physical properties desired for organic ant-reflective coating include high absorbance to light and radioactive rays, no intermixing with the photoresist layer (being insoluble in photoresist solvents), no diffusion of low molecular substances from the anti-reflective coating into the topcoat photoresist upon baking under heating, and a higher dry etching rate than the photoresist.
In recent years, in order to solve interconnection delay that has become clear with miniaturization in pattern rule of semiconductor devices, it has been considered to use copper as interconnect material, and to apply Dual Damascene process as Interconnect forming method on the semiconductor substrate. And, in Dual Damascene process, via holes are formed and an anti-reflective coating is formed on a substrate having a high aspect ratio. Therefore, the anti-reflective coating for use in this process is required to have filling property by which holes can be filled without gap, flattening property by which a flat coating can be formed on the surface of substrate, and the like.
However, it is difficult to apply organic material for anti-reflective coating on a substrate having a high aspect ratio, and in recent years, material with particular emphasis on filling property or flattening property has been developed (see, for example Patent Documents 1, 2, 3 and 4)
In addition, in the production of devices such as semiconductors, in order to reduce poisoning effect of a photoresist layer induced by a dielectric layer, JP-A-2002-12847 discloses a method in which a barrier layer formed from a composition containing a crosslinkable polymer and the like is provided between the dielectric layer and the photoresist layer.
As mentioned above, in the recent manufacture of semiconductor devices, in order to attain several effects represented by anti-reflective effect, it comes to provide an organic underlayer coating formed from a composition containing an organic compound between a semiconductor substrate and a photoresist layer, that is, as an underlayer of the photoresist. And, in order to satisfy required performance for underlayer coatings for which the diversity is increased, it is always required to develop new underlayer coatings.
In the meantime, an anti-reflective coating forming composition containing a saccharide compound is known. For example, an anti-reflective coating forming composition containing a cellulose compound is known (see, for example Patent Documents 5 and 6). Is also disclosed a pattern forming process by use of an a water-soluble anti-reflective organic coating comprising burrane being a polysaccharide as a main component (see, for example Patent Document 7). In addition, an anti-reflective coating material containing a polysaccharide having silyl substituents is disclosed (see, for example Patent Document 8).    Patent Document 1: JP-A-2000-294504 (2000)    Patent Document 2: JP-A-2002-47430 (2002)    Patent Document 3: JP-A-2002-190519 (2002)    Patent Document 4: WO 02/05035 pamphlet    Patent Document 5: WO 99/56178 pamphlet    Patent Document 6: WO 02/071155 pamphlet    Patent Document 7: JP-A-60-223121 (1985)    Patent Document 8: JP-A-2002-107938 (2002)